The purpose of the study is to evaluate the influence of qualitative cognitive differences (cognitive style) as a mediator between environmental circumstances (including ethnicity) and achievement measures. The concept of cognitive style is examined, particularly as it relates to school achievement differences between different sub-population groups. Literature which discusses the relationship between demographic variables such as race, sex, ethnic background and socioeconomic status is summarized. This literature is then expanded upon and applied, along with the concept of cognitive style, in comparing school achievement differences of Maori and Pakeha children from similar environmental circumstances in New Zealand. Hypotheses derived from the literature surveyed are tested against data collected for the Maori-Pakeha study. Findings are presented in comparative tables and discussed, and a copy of a cognitive style test is appended. It is suggested that the influence of school environments on preferred modes of cognition is probably strong enough to overcome any differences arising from socialization due to ethnicity. (Author/EB)